Global Patent Index - EP 0238041 A3

EP 0238041 A3 19890315 - PHASE LOCKED LOOP CIRCUIT

Title (en)

PHASE LOCKED LOOP CIRCUIT

Publication

EP 0238041 A3 19890315 (EN)

Application

EP 87103845 A 19870317

Priority

JP 5995686 A 19860317

Abstract (en)

[origin: EP0238041A2] The circuit uses a reference signal ( @r1) and a response control signal ( @c1) with a preset transition time, and comprises a voltage-controlled oscillator (58) to produce a signal ( @v1) variable in phase, a phase detecting circuit (10, 12, 14) delivering up (S3) down (54) pulses to a first (16) and a second (32) charge pump circuit. Each of the charge pump circuits has three states. A first first state to advance the phase of the variable-phase signal, a second state to retard the phase of the variable-phase signal, and a third state to maintain the phase of the variable-phase signal. The circuit further comprises a response control circuit (26, 28) responsive to the response control signal for maintaining the second charge pump circuit in the third state at a time subsequent to a phase difference detect period, thereby modifying the rate at which the voltage controlled oscillator responds to the up down pulses.

IPC 1-7

H03L 7/10

IPC 8 full level

G11B 20/14 (2006.01); H03L 7/08 (2006.01); H03L 7/089 (2006.01); H03L 7/091 (2006.01); H03L 7/093 (2006.01); H03L 7/10 (2006.01); H03L 7/14 (2006.01)

CPC (source: EP US)

H03L 7/0893 (2013.01 - EP US); H03L 7/10 (2013.01 - EP US)

Citation (search report)

  • [X] EP 0164806 A2 19851218 - PHILIPS NV [NL]
  • [A] IBM TECHNICAL DISCLOSURE BULLETIN, vol. 26, no. 7B, December 1983, pages 3752-3753, New York, US; R.L. COBURN et al.: "Rotational frequency detector"
  • [A] IBM TECHNICAL DISCLOSURE BULLETIN, vol. 16, no. 11, April 1974, pages 3719-3722, New York, US; K.A. SHIDLER: "Rapid synchronization circuit for a phase-lock oscillator"

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0238041 A2 19870923; EP 0238041 A3 19890315; EP 0238041 B1 19961030; DE 3751937 D1 19961205; DE 3751937 T2 19970522; JP H0787362 B2 19950920; JP S62216420 A 19870924; US 4774479 A 19880927

DOCDB simple family (application)

EP 87103845 A 19870317; DE 3751937 T 19870317; JP 5995686 A 19860317; US 2681187 A 19870317